ISLAMABAD  Pakistan’s top court ordered the arrest of the prime minister in a corruption case Tuesday, the latest clash between the government and a judiciary that has repeatedly pressured the country’s political leaders.

The Supreme Court order against Prime Minister Raja Pervaiz Ashraf was related to a case involving private power stations set up to provide electricity to energy-starved Pakistan. The judges are investigating allegations that the bidding process was marked by corruption.

Chief Justice Iftikhar Chaudhry ordered the arrest of 16 people involved in the case, including Ashraf, who previously served as minister for water and power, said the written court order.

An adviser to the prime minister, Fawad Chaudhry, said any attempt to arrest the prime minister would be unconstitutional since he enjoys immunity from prosecution while in office.

“We consider it a judicial coup, and it is part of a greater plan to derail democracy,” Chaudhry said.

The Supreme Court clashed repeatedly with the government over the past year, especially over an old corruption case against President Asif Ali Zardari in Swiss courts. Pakistan’s top court convicted Ashraf’s predecessor, Yousuf Raza Gilani, of contempt of court for refusing to reopen the case and ousted him from office.